I try to duplicate a form in my Designer with all the elements on it, that i have not to do the huge Job again of designing the full form again. I need only a few little changes on this form copy to do, so i do not want to design the same again from new. If i click on the form "copy" and then do "paste" on my Project the full Project is destroyed forever and a lot of error Messages Pop up about the form copy. I had to throw my Project afterwards since there's no undo of that action possible. Since this was a huge loss of work I decided to ask the question:
How do I valid copy/duplicate an existing form in the designer without errors afterwards appearing?
You should duplicate the form file, then change the class name in the copy in both the .cs and the .Designer.cs files.